I've got Dovecot 2.2r5 (Ubuntu package version 2:2.2.0~rc5-0~auto+1 from the "testing-auto/dovecot-2.2" repository on xi.rename-it.nl) running on a brand-new Ubuntu 12.04.2 server.
I'm trying to configure Dovecot (using the "mdbox" mailbox format) to allow folders to contain both messages and sub-folders. However, it's not working consistently.
I need to have folders with both messages and sub-folders because I'm trying to migrate mail from an existing (but soon-to-be-retired) Cyrus server, and the existing body of mail has folders of this sort.
I'm currently using the following configuration line:
mail_location = mdbox:~/mdbox:DIRNAME=.indexes:INDEX=~/mdbox/indexes
and am using the Larch program to do an IMAP-to-IMAP copy of one of my family member's mail from the old Cyrus server to the new Dovecot server. When I examine the "mailboxes" directory tree, I see some directories that (correctly) contain both the renamed ".indexes" directory and also directories for IMAP subfolders. However, the Larch output is showing many errors of the form "mailbox cannot contain messages", and some of the messages could not be migrated because of this problem.
Am I doing something wrong? Or is the "folders containing both messages and sub-folders" feature simply broken for the "mdbox" format -- meaning presumably that I'll be forced either to use the Maildir format, or else abandon Dovecot entirely and install Cyrus on my new mail server instead?
Rich Wales richw@richw.org